In the second phase of this project, we plan to pursue six interrelated studies. 1) To separate organelle-specific tubulin subunits, high resolution isoelectric focusing and also sodium do- and tetradecylsulfate electrophoresis will be applied to ciliary, flagellar, and cytoplasmic tubulin fractions. 2) Tubulin particulates from marine eggs will be isolated and compared biochemically with that now available from brain homogenates. 3) The putative ciliary assembly cofactor protein "band-20" will be isolated and characterized in terms of its relatedness to and co-polymerizatio with tubulin. 4) Cytoplasmic dynein, now identified in brain, will be purified and its association with microtubules and membranes explored. 5) Ciliary membrane tubulin will be characterized further in terms of isoelectric point and differential detergent binding. 6) Iontophoretically-introduced vanadate anion will be employed to evaluate the possible function of ciliary movement in sensory transduction and dynein in dividing cells.